Explosive-engine.



0.1. MARTIN.

EXPLOSIVE ENGINE.

APPLICATION man JULY 25, 1918.

1,280,058. I PatentedSept. 24,1918..

WITNESSES A TTOR/i/EYS DOUGLAS 3'. MARTIN, OF NEW YORK, N.

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' Specification of Letters Patent.

Application filed July 25, 1918. Serial No. 246,790.

To all whom it may concern:

Be it known that l, DOUGLAS J. MARTIN, a citizen of the United States, and a resident of the city of New York, borough of Manhattan, in the county and State of New York, have invented a new and Improved Explosive-Engine, of which the following is a full, clear, and exact description.

This invention relates to internal combustion engines and has for its general objects to provide an improved construction whereby the crank of the power or work stroke piston will be in its best angular position for receiving the maximum thrust from the explosion of the fuel charge while the latter is at the best degree of compression at the time of ignition, this result being brought about by an auxiliary piston which lags a certain number of degrees in its movement with respect to the working piston, so that as the latter moves outwardly from its in-.

working piston.

Another object of the invention is to so construct the auxiliary piston as to form with the engine cylinder a fuel mixing chamber into which fuel and air are introduced from a carburetor, so that the mixture will cool the walls of the piston and at the same time the heat imparted to the mixture will effectively gasify the liquid fuel particles before passing to the combustion chamber of the engine.

With such and other objects in view, the invention comprises various novel features of construction and arrangement of parts which will be set forth with particularity in the following description and claims appended hereto.

In the accompanying drawing, which illustrates one embodiment of the invention and wherein similar characters of reference indicate corresponding parts in both the views,

Figure 1 is a sectional view of the engine; and

Fig. 2 is a diagrammatic view showing the relation of the working piston crank to the auxiliary piston operating eccentric at the time the explosion of a charge takes place.

Referring to the drawing, 1 designates a cylinder of any approved construction which has a mixture inlet port 2 controlled by a valve 3, an exhaust port 1 controlled by a valve 5, and an igniter 6.

lVithin the cylinder 1 are the working and auxiliary pistons T and 8, respectively, arranged in concentric relation, with the latter surrounding the former. The working piston 7 is connected with a rod 9 which is connected with the crank 10 of the power shaft 11 of the engine. On this shaft are eccentrics 12 with which engage eccentric straps 13 having extensions 14 that are pivotally connected at 15 with the tubular auxiliary piston 8. As shown in Fig. 2, the high point a of each eccentric is considerably behind, say thirty-six degrees more or less, the point 6 of pivotal connection between the crank 10 and the piston rod 9, considered in the direction of rotation, as indicated by the arrow. This means that when the auxiliary piston is at the inner end of its stroke the main piston 7 will have traveled through the angle cd from the inner dead center, which is the best position for the piston to receive the explosive force of the gas to obtain a maximum efficiency. The movements of the two pistons are so related and their areas are also so proportioned that, as the main piston 7 moves outwardly from the dead center, the auxiliary piston will advance or move inwardly and maintain the compression of the charge at the most effective point. The cycle of movement of the pistons brings about the sucking in of a charge on one stroke, compressing the charge on the next stroke, firing the charge for the working stroke, and the expulsion of the spent gases on the succeeding stroke, in accordance with the fourcycle' principle.

The auxiliary piston is made use of to form a cooling jacket for the working pis- Patented Sept. 2 ft, 11918.

ton by conducting the fuel mixture therethrough, whereby the walls of the chamber are kept cool. For this purpose the external surface of the auxiliary piston is formed with a chamber 16 which cooperates with the cylinder 1 to form an annular compartment into which the fuel charge is drawn from the carbureter 17. Connected with this compartment is a pipe 18 which leads to the inlet port 2. The series of projections 19- on the auxiliary piston insure a more effective cooling action on the hot parts of the engine as well as effect a better mixing and vaporization of the fuel.

From the foregoing description taken in connection with the accompanying drawing, the advantages of the construction and method of operation will be readily understood by those skilled in the art to which the invention appertains, and while I have described the principle of operation, together with the device which I now consider to be the best embodiment thereof, I desire to have it understood that the device shown is merely illustrative and that such changes may be made when desired as fall within the scope of the appended claims.

Having thus described my invention, I claim as new and desire to secure by Letters Patent:

1. An engine including a cylinder, a working piston therein, a crank shaft connected with the piston, an auxiliary piston in the cylinder, and means connecting the auxiliary piston with the shaftto maintain a maximum compression in the cylinder while the working piston moves outwardly to a suitable point for ignition to take place.

2. In an engine, the combination of a cylinder, a working piston therein, an auxiliary piston surrounding the working piston, a crank shaft connected with the working piston, and means for operating the auxiliary piston from the main piston to maintain the compression of the charge as the main piston moves outwardly to a point for effective ignition of the charge.

3. In an explosive engine of the class described, the combination of a cylinder, a cenracemes tral working piston therein, an auxiliary piston in the cylinder surrounding the Working piston, a crank shaft connected with the working piston, and an eccentric device connecting the shaft with the auxiliary piston, whereby the latter maintains the compression in the cylinder while the piston moves outwardly to a point of ignition of the charge.

4; In an engine of the class described, the combination of a cylinder having a combustion chamber, a main piston in the cylinder, an auxiliary compression-maintaining piston in the cylinder and cooperating with the latter to form a chamber, means for supplying a fuel mixture to the chamber, whereby the mixture cools the pistons and cylinders, and valve-controlled means between the lastmentioned chamber and the combustion chamber of the cylinder.

5. In an engine of the class described, the

combination of a cylinder having a combus- DOUGLAS J. MARTIN. 

